Alright guys. So basically, as you can probably tell this is a guide for the Cow, Alistar, and it is a sort of special build, which I use, and would like for you guys to get to know.
Basically it focuses on damaging massively early game and mid game, while once it turns late game, you'll want to look at becoming more tanky.
I suppose you might call it an AP Off-Tank build.(Credits to the original owner of the picture I used to create this - Found on League of Legends Wikia)

10/06/14:
This is my standard choice of masteries for AP Alistar.
The main focuses of these masteries' Offense Tree are getting the Magic Penetration and the Burning Embers(Improved Ignite) to get some extra AP during laning phase. This is less important later in the game, however.

The 6 points in the Defense Tree makes it a lot easier for you to take just a bit more damage early on, and gives you an extra 6 Armor and 6 Magic Resistance.

The Utility Tree is however the place where we invest the most points. You will first off want to prioritize the reduced death time above the increased health and mana regen, since the increase in health and mana regen isn't significant enough at all to overgo 15% less time spent dead. Second, you'll want the increased EXP gain above the increase in Mana, as that isn't all that usefull to anyone but Mana Stackers like Ryze, for example. Finally you want to get the extra Mana Regen, which will work well with Doran's Ring early game, the increased Buff Time, and finally the lower cooldown on your summoner spell Flash.

10/09/11:
This set of Masteries are also a nice choice for Alistar, however I usually prefer to use the set above.

The Offense Tree is just the same as the set above, without any changes.

However, in the Defense Tree we have added 3 more points in Strength of Spirit Mastery, which gives you a slight bit of an increase in health regen, however you don't really feel this before you get your hands in Glacial Shroud and then afterwards Frozen Heart.

Because of the extra investment in the Defense Tree, the Utility Tree must suffer from a bit of a drain. Basically one of the sometimes more important factors is that you don't get to take the Blink of an Eye(Improved Flash) Mastery. And another suffering you'll be taking is the slight reduce in the Mana Regen gained from Meditation.

Greater Mark of Insight
These Marks will help you deal some more damage, and early game, that is something you'll want to appretiate. Basically, it directly ignores 9 of the enemy's Magic Resistance, which will be a really great help against the magic-based squishies out there. (Many people run around with 30 Magic Resistance for a long time of a game, unless getting Banshee's Veil etc.)

Greater Seal of Resilience
These Seals will give you some additional Armor. Combined with the 6 Armor from the Hardiness Mastery, that will give you, at level 1, a bonus of 19 Armor. This will protect you pretty well against any physical damagers you might be facing in your lane.

Greater Glyph of Potency
Basically, you get these only to increase your early game damage output. This is something you'll need for your W + Q combo to be effective at early game. It also gives you a nice amount of AP after acquiring 3x Doran's Rings as according to the build.

Greater Quintessence of Potency
Same as with the Glyphs.
Basically, you get these only to increase your early game damage output. This is something you'll need for your W + Q combo to be effective at early game. It also gives you a nice amount of AP after acquiring 3x Doran's Rings as according to the build.

Other choices for Glyphs: Greater Glyph of Cooldown Reduction: These will give you a decent amount of early game Cooldown Reduction, and later, after getting both Boots of Lucidity and Frozen Heart it will bring you to the cap of Cooldown Reduction, and actually give you an additional ,85% which will of course not count for anything. Greater Glyph of Scaling Ability Power: These will give you Ability Power along the laning phase, instead of getting it directly at lvl 1. This might be viable if you are solo laning at top, however not if you're going mid, since then you will want to focus on bursting the enemy down, like you will in a normal lane.

Note: I find that there are no replacements to be made when it comes to Marks and Quintessences. Glyphs can be changed, but you need at least the 15 AP from the Quints, and there are as far as I see it, no better choice for this build, when it comes to Marks.

Recommended Choices

Ignite
Ignite is really usefull Summoner Spell, not only because of the DoT, but also because of the healing reduction. This is a nice counter to guys like Swain, Vladimir, Tryndamere and all kinds of spell vamp stackers out there. Furthermore, with the Burning Embers Mastery, this enables you to get an additional 10 AP to work around with - You can claim this in the very first encounter with the enemy, or you can save it to try and get a kill.

Flash
Flash is one of the most appretiated Summoner Spells that exist. It simply enables you to do so many wonderous things, like flashing out of combat on the tip of dying, or you can choose to use it more creatively by trying to steal Dragon kills and Baron Nashor by flashing over walls. Finally, you can use it to catch a fleeing enemy by flashing and then using Pulverize.

Other Possible Choices

Teleport
Teleport is a pretty solid choice and can be used instead of Ignite. You will suffer from not being able to stop enemy heavy health regeneration abusers on the enemy team as well as being able to put a nasty DoT on an enemy, and last but not least it will cost you the extra 10 AP you gain when Ignite is on cooldown. However, in turn, you will achieve the capability of truly being an all map presence. If you want to roam(For this I suggest adding some Gold/10 items to the build such as Philosopher's Stone and Heart of Gold), then this is indeed a good choice for a substitute to Ignite. This spell can also help if you feel that solo laning might be hard on you, even though Alistar's solo laning capabilities are very good.

Ghost
You can choose to go with Ghost instead of Flash if you like, and it is indeed a decent choice, since it can both help you catch the enemy with your W + Q combo(Explained later), but it can also help you get to safety. In my eyes however, I'd, for Alistar, always choose Flash over Ghost, since being able to just Flash into the middle of a fight and start throwing people around is really something I, personally, wouldn't want to throw away for a speed buff. It is however only a matter of preferance, and you can use Ghost if you wish or rather prefer to do so.

Cleanse
Cleanse is also a decent choice for Alistar, as you will, before you get to start on the tanky side of this build, might find yourself getting focused by stuns a lot. In that case, Cleanse can be the thing you need. It is truly a nice thing, finding yourself being target of all the enemy CC, to quickly use Cleanse, and then pop your Ultimate, Unbreakable Will, to be able to actually take that damage and CC like it was nothing. Trust me on this: With this, the enemy will regret if they choose to target you to be stunlocked. It will only be a waste of their mana and will give them unneeded cooldowns.[/center]

W > Q > E > W > W > R > W > Q > W > Q > R > Q > Q > E > E > R > E > E

This is my standard way of leveling Alistar's skills. Basically you want to focus on Headbutt because of the fact that it the skill of yours that owns the highest AP ratio, and as such it is your strongest damaging source. Because of this, you want to level it oftenly to make the base damage follow along as you also, by time increase your amount of AP.
Your Q, Pulverize is your second most important skill(Aside from Ultimate, of course), and is the key to your W + Q combo(Explained later).
The reason you don't focus much on the E, Triumphant Roar is the fact that it simply isn't valuable enough to replace the cooldown reduction you gain each time you level Q and W. Having these skills on a low cooldown is key in teamfights. Imagine not being able to finish that fleeing enemy with headbutt because your missing maybe 2 seconds of cooldown?
This skilling sequence goes for Roaming and playing Mid as well.

For Solo-Laning at Top

Q > W > E > Q > W > R > Q > W > Q > Q > R > W > W > E > E > R > E > E

This sequence, as you can read, is specifically and thus only in the case of you playing as the Solo Laner at the Top Lane.
The difference from this skilling sequence and the one above is, that you in this one will try to mix up the leveling of Pulverize and Headbutt. The reasoning for focusing some more on Pulverize in this case, is that, it is one of the things that makes it easy for Alistar to solo lane. You do this buy getting into the middle of the minion wave when being pushed, then using Pulverize, knocking them all up and damaging them, whereafter your passive, Trample will do it's AoE damage on them, and approximately with one autohit on each ranged minion, that's at least 3 minion kills for you each wave that the enemy pushes.

Explain why it's good. Mention if they might wanna go with a dynamic sequence and some situations where a certain way is better than others.

x 3Doran's Ring
This is probably something that you might be wondering quite a bit about, however Doran's stacking is a widely spread and something used quite often to get that extra early bulk from the HP, as well as the Doran's item's extra bonuses. In this case, it's all about the Doran's Ring. Basically, I've found that Doran's Ring x 3 makes for a nice amount, as 2 would be too little, not adding enough HP to Alistar, however 4 is quite overdoing it - This is where it doesn't matter that much anymore. Let's also not forget the increase in AP. With all 3 Doran's Rings, you get an extra 45 AP. From your runes, you should have roundly 25 AP, and whenever your Ignite is on cooldown, that should grant you, roundly speaking 80 AP. That is pretty decent, when also considering the effective mana regen as well as the 300 HP you get on top of that. You become bulkier, and you deal more damage, what else is there to say?

Ionian Boots of Lucidity
Basically the reasoning for choosing these Boots above so many other choices are Alistar's rather tough cooldowns. Their length can't be ignored, and that is why I feel that it is necessary to kick in with some Cooldown Reduction very early in the game. Since the build focuses on being an early death-machine, and a later Strong, Tanky Battlemage(So to speak), I feel that getting Glacial Shroud early would be kind of a waste of money.Other choices: There are however other choices for boots that you can take. The other viable options for you to take, are Sorcerer's Shoes and Mercury's Threads. Sorcerer's give even more Magic Penetration, which will make it 29 with your runes, which is pretty nice against those squishy ones with only 30 Magic Resist. That will actually, against those foes, almost give you a full True Damage output on them. Mercury's Threads on the other hand help you quite well on the defensive side, by reducing incoming CC by 35% which can be really helpful. I recommend getting these if you find that the enemy team has extraordinarily much CC.

Rabadon's Deathcap
The strongest of all the AP items out there. It really adds an amazingly large punch to Alistar's abilities. That is, making your W + Q combo(Explained later) a lot stronger, but also increasing the amount of damage your passive, Trample, will do to enemies, after using an ability.

Lich Bane
This is one of the most important items for this build. And you will want to keep in mind that you are in possession of it, and use it wisely. For example you can easily get the last hit on that fleeing enemy without neither Headbutt nor Pulverize. It can be done just by using Triumphant Roar, Flashing to the enemy, and then just hit them with one physical attack. That will, after obtaining both the RD and the LB, deal something like a little below 400 magic damage, which at least in a few cases will be enough to make that last hit on the enemy. If it isn't enough, and they survive the hit with just a slipper of health after all, just stick close to them, as Trample should be capable of doing the rest.
However! That nice little passive is not all this item will grant you! It also gives you a passive extra 7% of movement speed! That is something that's really awesome for Alistar, as catching up to fleeing enemies can be something that can change a teamfight completely. It might also come as a surprise to the enemy how fast this cow can be.

Force of Nature
This is a very strong item for Alistar. Not only is it the item with the highest amount of MR given to the wearer, however, what else? Let's see... It gives extra Health Regen? Nah, that's not that important, really, since you have Triumphant Roar. But then what is it? Extra movement speed by 8%!! Yes! That's it! This is one of the reasons this item fits especially well in this build, since, as AP Alistar, you will like to be able to catch up to your enemies to deliver that final blow with Headbutt. This is a job this item does extremely well, since you already have the bonus movement speed from Lich Bane.

Frozen Heart
Frozen Heart. Yes. Let's see. It gives you 99 Armor, which is the second highest an item will ever give, only outtrumphed by Thornmail, which gives only 1 more. Aside from the high amount of Armor, it also gives you 500 mana. This is a pretty solid counter to Alistar's mana problems, even if it doesn't keep him from running out of mana. That is something the blue buff will have to help out with. Next thing you get is Cooldown Reduction. That is something you'll appretiate a lot, indeed. It will, together with Ionian Boots of Lucidity grant you 35% Cooldown Reduction. A blue Elixir will bring that to 40%, which is the cap. Finally you get a Passive, that reduces nearby enemies' Attack Speed by 20%. This is a pretty nice counter against enemy physical carries, but elsewhat doesn't really benefit you all that much, as you can always just pop ulti to reduce incoming damage.

Rylai's Clystal Scepter
Preferably your final item. You start off with the Gian't Belt, and then finish it in one go, in the next purchase. It can be discussed whether or not you should get this item earlier or not, however I find that getting your resistances up and going is more important than just getting that little bit of extra HP. If the game happens to come as far as this, you should be kicking butt pretty hard already(Excuse my language), however getting this, is just the final icing on the cake. It enables you to slow your enemies with every single spell you use on them. This is something that is really, really usefull for Alistar's movepool. The enemy will be slowed after you Headbutt them into your teammates, so that they will have that much less a chance of surviving, and everything that gets in contact with your Pulverize will not only be knocked up, but also be slowed afterwards. However, none of these things are the most frightening. It is by far the slow on Trample that will make the greatest impact. Basically, your enemies will be slowed from you just healing yourself, because of this lovely little Passive AoE. That is something that you should definitely take advantage of when you are in a fight in possession of this item.

Benshee's Veil
Banshee's Veil is a possible substitute instead of Force of Nature. You gain some extra HP and Mana, and a passive that creates a shield for you every 45 seconds that will absorb one enemy offensive ability targeted at you or hitting you in it's path. What you lose is however a bit of Magic Resistance, the Health Regen as well as, the most important part about FoN: The Movement Speed increase.

Thornmail
You can choose to use Thornmail instead of Frozen Heart. Doing this will enable you to perfectly counter enemies with high Physical Damage output. Returning 30 % of recieved damage from auto attacks isn't all that bad, however you lose a lot of Mana on it, which Frozen Heart has, as well as the strong 20% Cooldown Reduction. If you do choose to go Thornmail, because of the enemy team being extremely oriented on Physical Damage, I suggest that you claim the Blue Buff as often as possible to make up for the lost CD Reduction.

Abyssal Scepter
This is another viable item for Alistar. Aside from helping your teammates through lowering the enemy's Magic Resistance, it helps all of your offensive skills do more damage. Furthermore Trample's AoE will get to do just that little bit more damage. It gives you AP and MR at the same time, which seems as a good deal, and the passive is as mentioned pretty good for you. I suggest getting this item after Force of Nature if the enemy team is very Magic Damage oriented. If not, then I suggest sticking to the original build and exclude this item.

Randuin's Omen
This item is something I've thought a long time about putting into the standard build. I ruled it out simply because Frozen Heart's Cooldown Reduction is so much more comprehensive compared to that of Randuin's. Besides, the 500 Mana can't be ignored either. Basically, Randuin's does however bring a lot of really awesome things with it. First of all, it's subitem or ingredient, Heart of Gold is one of the fewer items that bring you extra Gold over time. Getting this early might give you a slight advantage, although you should be farming fairly well, and at least scraping together some kills(Check Gameplay). Other than this, there is Randuin's Passive and Active. If someone hits you with a Physical Attack, they have a chance of getting slowed, and getting reduced Attack Speed, however the Active, ADDS a slow to surrounding enemies. This is what makes the item worth buying, perhaps in place of Frozen Heart. The Active can be used in combination with your W + Q Combo, whereas you'll use the slow right after knocking the enemy up, to make them stick around for just a bit longer. This is really strong, when you want to catch someone, and make sure your teammates can get there in time to kill the person with you, if not your combo just kills them right off.

Shurelya's ReverieShurelya's Reverie
Basically this item is here, simply because of two thing: The Cooldown Reduction and the Active. Obviously, the item adds to you some HP, HP/5, MP/5, however the Active is mainly what makes it viable. As you can read for yourself, it speeds up you and surrounding teammates by 40% for 3 seconds. This is kind of like a free short-term Ghost, except this movement speed buff is actually a lot stronger than that of Ghost's.

Okay, so basically, you will want to, depending on your lane partner, try to go to your bush, and await the enemy, attempting an FB. You should attempt this if your laning partner is one with a viable slow, or a Jump of some sort. A good choice for a partner with a slow could be for example Ashe( Volley) or Xin Zhao( Audacious Charge), and a choice for someone with a Jump of a sort could be for example Jax( Leap Strike) or Master Yi( Alpha Strike).

If you find that you have the right laning partner with good potential for you and him/her to get the FB, enter your own brush, but don't enter the enemy brush. If the enemy wants the same as you(FB), there's a chance they'll enter your brush. If the enemy does that, attempt to go behind the enemy, and Headbutt them back into your teammate, who, by the way, is best to be some sort of DPS, so that they can deal some damage after you throw the enemy back. Also make sure that you get your hands on the right target(The most squishy one, or the one with lowest chance of getting away).

On your way to your lane, you should study your enemy team's Summoner Spells. Take note of anyone without Flash, and if you end up in a lane against one like this, make sure to make that person the focus, obviously unless it's a tank or very bulky character.

If you can see that it won't be possible to run behind them, don't be afraid to use Flash to get behind them, however before you do so, evaluate whether or not the target will be a sure kill or not. If they get away anyway, it hasn't been worth it. If the enemy is looking to get away with very low HP, pop Ignite to secure the kill. This will also give you an extra 10 AP for the next time you meet.

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During the middle of the laning phase you should always look for oppotunities to use your W + Q combo on the squishiest enemy on the lane. During the laning phase save your Ignite for until you can use it to kill someone. Wasting it just to get the 10 AP, is not recommended. You should always wait until you at least see a chance to get a kill with it.

Finally: Don't be afraid, if you're dominating your lane together with your partner, to push quickly, and then leave the lane unnoticed to gank @ Mid lane. This should of course only be done if the mid is in trouble. If your mid is doing good, there's not really much of a point in ganking, unless the enemy mid is overextending.

Alright, so when you are going mid, which is completely viable for this build, you should, as in the build, level Headbutt first, and basically, the more focused the enemy is one the minion lasthits, the more you should be focused on attacking them. Getting kills in mid is really not that hard with AP Alistar.

When you want to Headbutt the enemy, make sure to target the first, and then use Headbutt on them. Targeting them first will ensure you an extra Autohit on them before they fly away. After Headbutting them away, dealing moderate damage to them, make sure that you're not needlessly catching any enemy minion agro. If some of the enemy minions started targeting you, simply run away from them, and focus on lasthitting. The more you harass your enemy the more afraid they'll be to come close to you.

Please note that you are capable of doing two things:
--> Target the enemy --> Headbutt --> Moderate damage (Less Mana Used)
or:
--> Target the enemy --> Headbutt + Pulverize --> Awesome Burst --> Autohit them a few times and let your Passive, Trample work a bit on them (More Mana Used)

Always make sure you keep your Mana at a moderate point. Keeping it steady at around half is mostly the best. Make sure that while you don't want to run out of Mana, also don't ever get to max Mana. If your mana is full, you haven't harrassed enough. Don't be afraid to use W + Q if you have a lot of Mana.

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Pushing: Basically, if you've just killed the enemy at Mid, just PUSH. It's a good opportunity to deny your enemy some EXP, and you get gold from it, so hell, why not? However be wary of misses, as well as the jungler if you got low from the fight with the enemy. When choosing to Push after killing the enemy you should, if your sort of low, make sure that you have Flash ready. If you do not, and you're at 1/6 health or below, you should recall.

How to push quickly: Use Pulverize, while standing between the enemy melee and ranged minions(See more under Tips and Tricks).

While playing in mid, don't be afraid to push a lot, unless you see a chance to completely lock down your enemy. This can be done against the more squishy mids out there, like for example Ashe. A combo and she's practically half way dead. This is something, after showing them the effect one or two times, that can be used to deny your enemy exp. If this is doable, that is the only case of which you should bother not to push.

This is a role that you should happily take, no matter if the enemy team has a jungler or not. If they do not it, will however be more of a challenge, and that challenge is what I am going to describe here.
If you're against another solo laner the way to play is pretty much the same as what I've described in the section above(Gameplay - Laning Phase @ Mid).

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Alright, so, as said, I'll now explain a bit about how you should do things, when you're facing a 1v2 situation at top lane. First of all, since you won't be getting that much from Headbutting one person(Since then the other one might deal damage to you), you should level Pulverize first, and simply await the enemy untill they have pushed towards you. You'll want to do the pushing trick I mentioned in the previous chapter, which can also be found under Tips and Tricks. This is however something you should only do, either if the enemy minions are at your turret, or if something like 6 ranged minions are stacked up and are pushing forward.
Once you get lvl 2, however, that is when you might want to look at things more offensively. Lvl 2 is still quite early, however if the enemy has decided to put someone squishy enough for you to burst at top, you should definitely try doing some damage with your W + Q combo. Also, if possible, try to attack the squishy one while that person is standing near the other champion on the lane. That will leave it impossible for the other champion to deal much damage to you, before you can make it to run back, and of course it will also deal some damage to the less squishy opponent.

If you feel that you have great control over your solo lane, you can basically play around with them quite a lot. Personally, I've some times done Double Kills several times in a match while solo laning at top. The enemy always seem to underestimate your power, and that is something you, as an AP Alistar player should take great advantage of.

Alistar is an amazing initiator. The enemy will be sure to know of your W + Q combo, and they know that if you catch any one of them, with the help of your teammate that may mean a quick death, which will give an advantage in an upcoming teamfight. Basically, you should be afraid to be the one to make the first move, however, if the enemy team seems to react offensively, be sure to use your Ultimate BEFORE you get stunlocked.

During the teamfight, you should try to find a balance between being focused completely by everyone on the enemy team(With CC and what not), and not getting noticed at all. You want to make them know you're there, which you do by knocking people up, Headbutting people around, however, don't towerdive without your teammates being able to keep up, and don't just dive towards the carry hiding out being her/his teammates. This will just split you from your team, and mean a needless death on the scoreboard, not to mention your team missing you in an eventual upcoming teamfight.

You'll want to focus the squishies. If you have someone else on your team to initiate, perhaps a tank like Amumu, you should try to save your combo for when the enemy carry comes out to play. Quickly burst the carry down, and you might just have won that teamfight, depending on how much the carry is worth on their particular team, of course.

--> First of all, make sure that you, during Champ Select mark out that you are playing Alistar as an AP. Your teammates should be able to realize that by your Ignite and Flash, but it's best to make sure your teammates don't mistake you for a Tank or a Support. You are AP. That's just how it is. You may want to add that you will be getting tanky late game, though, but also that they shouldn't rely on you to tank before you've gotten your FoN and Frozen Heart.

W + Q: Basically, Alistar has quite the frightening combo in just two of his abilities, Headbutt and Pulverize. By using Headbutt on a target, and then, while on the way to charge them, using Pulverize, the enemy will recieve damage from both spells, you will have closed the gap between you and the enemy, as well as knocking the enemy into the air. You should take use of this combo right from lvl 2, once you have both spells. Enemies will get scared.

Harrassing with Headbutt: When at lvl 1, or if you don't have mana for Pulverize or an alike situation, make sure that you target the enemy with your autohit before you Headbutt them. This will make Alistar autohit the enemy once before they fly away.

Judge your own mortality. Don't start diving into a 1v5 unless you're absolutely certain that your Ultimate will be enough to keep you alive; remember: It's only a matter of 7 seconds. And you still do take some damage in that period of time.

If you notice that the enemy is fond of spending their CC on you, be glad, since it helps your teammates, however, keep in mind to remember to use Ulti, if there is an upcoming Stunlock on it's way towards you. (Example: Malzahar's Ultimate. If you don't manage to use Ulti before his locks you down, then you might just be done for)

Use Trample to your advantage: Wisely. You can kill of people only with Trample. You don't necessarily need your Headbutt nor Pulverize to kill and opponent. Take use of Sheen/Lich Bane, and Trample to kill enemies. Using Triumphant Roar is a good, easy way to trigger both Sheen/Lich Bane and Trample.

Always make sure that you have plenty of Mana in your storage. Make sure you have enough Mana before you attempt your W + Q combo. It will look silly if you end up Headbutting an enemy away from your team because you don't have enough Mana for Pulverize. That'll just lead to being called "noob" and "failz0r", etc.

Use Pulverize when you want to push quickly. Once two minion waves have met, make sure they've all found a target which isn't you, then place yourself between the enemy melee and ranged minions, and use Pulverize, effectively hitting them all, and then let Trample work on them. If it's later in the game, you'll be able to one hit the ranged minions with Pulverize and Trample, however at early game, you might need to give them an autohit each.

If you have read all or at least most of what I've had to say in this guide, I would like to thank you a lot for reading all of this :)

Also, I have nothing against constructive critisism, but I do not approve of people voting down because they want to use other Runes or Masteries, or even Summoner Spells. I did mention other choices, so I see not why one would downvote of such things, but yeah :3 As I've put a mark on *Require comment to vote* I'll at least, hopefully know of the reason of your downvote if you do choose to make one ^^'

As I said, thanks for reading, and I hope you'll have great success and maybe have learned something from my guide :) See you around!

League of Legends is a team based, real time strategy game set in a mythical world of swords & magic where epic battles decide the fate of mystical nations. Game players take on the role of a Summoner who conjures and controls champions to fight for them at the Institute of War. During game play champions gain experience and items to enhance their skills and abilities. How players develop and play their champions can be the difference between a crushing defeat or a glorious victory!